Your chao must have reincarnated twice (be on its third life) before you can try to make it into a Chaos chao. When it rehatches on its third life, give it only one of each animal (21 total) and NO chaos drives, and then change its alignment to whatever you want it to become. When it evolves it will become either a Hero Chaos chao (aka Angel) Dark Chaos (Devil) or Neutral (Light). It doesn't matter at all what type it was on its previous life.
~ Crazy C Lea